The efficiency of 1 M NH4Cl and 2 M NaCl for the isolation of pathogenic Nocardia from soil.

Abstract

The present paper reports an improvement to the classical method of the paraffin bait, by the usage of 1 M NH4Cl or 2 M NaCl to eliminate contaminant microflora of soil. The purpose is to introduce a change in the paraffin bait method in order to reduce time required to isolate pathogenic strains of Nocardia from their natural sources. For this study three main criteria were used: a) Determination of the inhibitory effect of different concentrations of salts on soil microflora; b) The tolerance of Nocardia brasiliensis, Nocardia asteroides and Nocardia caviae (Nocardia otitidis caviarum) strains to these chemical inhibitors; c) Determination of the efficiency of salts in the isolation of Nocardia from soil when strains are grown on paraffin baits.